FAILED: patch "[PATCH] NFSD: NFSv4 file creation neglects setting ACL" failed to apply to 6.1-stable tree

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 913f7cf77bf14c13cfea70e89bcb6d0b22239562
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2025122941-crusher-hamstring-d100@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 913f7cf77bf14c13cfea70e89bcb6d0b22239562 Mon Sep 17 00:00:00 2001
From: Chuck Lever <[email protected]>
Date: Tue, 18 Nov 2025 19:51:19 -0500
Subject: [PATCH] NFSD: NFSv4 file creation neglects setting ACL
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

An NFSv4 client that sets an ACL with a named principal during file creation retrieves the ACL afterwards, and finds that it is only a default ACL (based on the mode bits) and not the ACL that was requested during file creation. This violates RFC 8881 section 6.4.1.3: "the ACL attribute is set as given".

The issue occurs in nfsd_create_setattr(), which calls nfsd_attrs_valid() to determine whether to call nfsd_setattr(). However, nfsd_attrs_valid() checks only for iattr changes and security labels, but not POSIX ACLs. When only an ACL is present, the function returns false, nfsd_setattr() is skipped, and the POSIX ACL is never applied to the inode.

Subsequently, when the client retrieves the ACL, the server finds no POSIX ACL on the inode and returns one generated from the file's mode bits rather than returning the originally-specified ACL.

index fa46f8b5f132..1dd3ae3ceb3a 100644
@@ -67,7 +67,8 @@ static inline bool nfsd_attrs_valid(struct nfsd_attrs *attrs)
 	struct iattr *iap = attrs->na_iattr;
 
 	return (iap->ia_valid || (attrs->na_seclabel &&
-		attrs->na_seclabel->len));
+		attrs->na_seclabel->len) ||
+		attrs->na_pacl || attrs->na_dpacl);
 }
 
 __be32		nfserrno (int errno);

From: Chuck Lever <[email protected]>

[ Upstream commit 913f7cf77bf14c13cfea70e89bcb6d0b22239562 ]

An NFSv4 client that sets an ACL with a named principal during file creation retrieves the ACL afterwards, and finds that it is only a default ACL (based on the mode bits) and not the ACL that was requested during file creation. This violates RFC 8881 section 6.4.1.3: "the ACL attribute is set as given".

The issue occurs in nfsd_create_setattr(). On 6.1.y, the check to determine whether nfsd_setattr() should be called is simply "iap->ia_valid", which only accounts for iattr changes. When only an ACL is present (and no iattr fields are set), nfsd_setattr() is skipped and the POSIX ACL is never applied to the inode.

Subsequently, when the client retrieves the ACL, the server finds no POSIX ACL on the inode and returns one generated from the file's mode bits rather than returning the originally-specified ACL.

---
 fs/nfsd/vfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index cdf73700d053..87a596fc6654 100644
@@ -1320,7 +1320,7 @@ nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	 * Callers expect new file metadata to be committed even
 	 * if the attributes have not changed.
 	 */
-	if (iap->ia_valid)
+	if (iap->ia_valid || attrs->na_pacl || attrs->na_dpacl)
 		status = nfsd_setattr(rqstp, resfhp, attrs, 0, (time64_t)0);
 	else
 		status = nfserrno(commit_metadata(resfhp));

2.52.0